Increasing Food Supply: Strategies & Sustainable Futures

Closing the Gap: Strategies for More Food

Feeding a world of over 8 billion people — soon to be nearly 10 billion — means producing more food, wasting less of what we grow, and doing it without permanently damaging the land and water systems that agriculture depends on. Geographers group the responses into two broad camps: high-technology, large-scale interventions that can increase production rapidly, and sustainable, locally appropriate approaches that work with natural systems rather than against them. Both are needed, and both carry trade-offs.

Strategies to Increase Food Supply

Irrigation brings water to farmland that would otherwise be too dry to cultivate. Around 40% of all food produced globally comes from irrigated land, which covers only 20% of the world's cropland. Modern drip-irrigation systems deliver water directly to plant roots, cutting water use by up to 50% compared with flood irrigation. Pakistan, Egypt and India depend on large-scale irrigation for their staple food supplies.

Aeroponics and hydroponics grow plants without soil — roots are misted with nutrient-rich water in aeroponics, or submerged in it in hydroponics. Both methods use up to 90% less water than conventional farming, produce higher yields per square metre and can be operated indoors year-round without weather risk. Their main limitation is high capital cost, making them most viable in wealthy urban contexts or where land is extremely scarce (such as Singapore).

The New Green Revolution applies biotechnology — including GM crops — to create varieties with higher yields, drought tolerance and pest resistance. Golden Rice, engineered to contain vitamin A, addresses deficiency affecting 250 million people. Critics raise concerns about corporate control of seed supplies, loss of traditional crop varieties and unknown ecological risks from gene transfer to wild plants.

Appropriate technology takes a different approach: simple, low-cost, locally maintainable tools matched to the resources available in LICs. Examples include the treadle pump (a foot-powered device that lifts groundwater for irrigation, costing around £25), improved grain storage sacks that cut post-harvest losses, and hand-operated seed drills that improve planting precision without heavy machinery.

Case Study: Indus Basin Irrigation Scheme, Pakistan

The Indus Basin Irrigation System (IBIS) in Pakistan is the largest contiguous irrigation network in the world. It draws water from the Indus River and its tributaries (the Jhelum and Chenab) through a system of three major dams (Tarbela, Mangla and Chashma), 19 barrages and over 58,000 km of canals to irrigate approximately 18 million hectares of farmland. Construction of the modern system began in earnest following the Indus Waters Treaty with India in 1960, which divided the rivers between the two countries.

Advantages of the IBIS:

• Pakistan produces around 90% of its food from the irrigated Indus plain, making the scheme central to the country's food security for a population of over 220 million.
• Major crops supported include wheat, cotton, sugarcane and rice — the scheme underpins Pakistan's agricultural export economy, with cotton textiles a significant export earner.
• The system creates millions of agricultural jobs across Punjab and Sindh provinces, supporting rural livelihoods.

Disadvantages of the IBIS:

• Waterlogging and salinity: over-irrigation has caused the water table to rise in many areas, leaving soils waterlogged and salt-encrusted. An estimated 6–10 million hectares of irrigated land is affected by waterlogging or salinity, cutting yields and in severe cases rendering land uncultivable.
• Water theft and inequity: farmers at the tail ends of canals often receive insufficient water because those upstream divert more than their allocation. This creates sharp inequalities between head-reach and tail-reach farmers.
• Glacial dependence: the Indus system relies partly on meltwater from Himalayan glaciers. As glaciers retreat under climate change, long-term water availability is threatened — an existential risk to a system Pakistan cannot afford to lose.

Moving Towards Sustainable Food Futures

Large-scale production can feed more people, but if it degrades soils, depletes water and harms ecosystems, it merely borrows against the future. Sustainable approaches aim to meet current needs without compromising future food security:

• Organic farming avoids synthetic fertilisers and pesticides, building soil health through compost and crop rotation. Organic soils hold more moisture and are more resistant to erosion, though yields per hectare are typically 20–25% lower than intensive equivalents.
• Permaculture designs farm systems that mimic natural ecosystems — mixing trees, shrubs, crops and animals so that each element supports the others. It requires minimal external inputs and is particularly suited to smallholder farmers in tropical regions.
• Urban farming uses rooftops, vertical gardens, allotments and community plots to produce food in cities, cutting food miles and improving access for low-income urban communities. Cities like Singapore, Detroit and Havana have developed significant urban food production.
• Sustainable fish and meat means choosing certified sources — Marine Stewardship Council (MSC) for fish, RSPCA Assured or organic for meat — and reducing overall consumption, especially of beef and lamb which have the highest carbon and land footprints.
• Seasonal food consumption matches purchases to what grows locally at the time, cutting the energy cost of heated greenhouses, refrigerated shipping and air freight. A locally grown tomato in July produces a fraction of the carbon of an air-freighted one in January.
• Reducing waste and losses is the cheapest way to increase effective food supply. The UN estimates that around one third of all food produced globally is lost or wasted — reducing this by half would be equivalent to feeding an extra 1 billion people without growing any more.

Local LIC/NEE Scheme: Sand Dams and Food Security in Makueni, Kenya

In Makueni County, semi-arid Kenya, the NGO Excellent Development has built hundreds of sand dams since 2002. A sand dam is a low reinforced-concrete wall, typically 1–4 metres high, built across a seasonal sand river. As floodwater flows over, it deposits layers of coarse sand behind the dam. Water is stored within this sand — not as an open reservoir, so evaporation is minimal. By 2023, Excellent Development had supported the building of over 800 sand dams across rural Kenya (including Makueni County), serving more than 100,000 people in a region that previously suffered severe seasonal water and food shortages.

Each dam costs roughly £6,000–10,000 to build, using local materials and community labour. The stored water allows year-round irrigation of small vegetable plots — onions, kale, tomatoes — transforming what was a single rain-fed harvest into multiple harvests per year. Women in particular benefit: they no longer spend three to four hours a day walking to distant water sources, freeing time for farming, education and income-generating activities. Soil moisture around the dam also increases, improving the productivity of rain-fed land downstream.

Conclusion

There is no single solution to global food insecurity. Large-scale irrigation like Pakistan's IBIS can transform national food security but brings long-term risks of soil degradation and climate vulnerability. Local schemes like Makueni's sand dams deliver immediate, sustainable benefits to communities most at risk — at a fraction of the cost. A food-secure future will require both approaches, alongside the cultural shifts of eating seasonally, wasting less and choosing sustainable sources.